Hard surface substrates such as stone, masonry, concrete, unglazed tile, brick, porous clay and various other substrates are used decoratively and functionally in indoor and outdoor environments. When untreated, these materials are susceptable to staining from water, oil, and foodstuffs such as ketchup, mustard, coffee, cooking oils, wine, and beverages and acid etching from acidic liquids such as orange juice and pickle brine. Several products exist in the marketplace for treating these substrates for oil and water repellency and soil resistance. Stone and tile treatment products useful for oil and water repellency are commonly a copolymer of a fluorinated monomer providing stain release and oil repellency, with a non-fluorinated monomer, for water repellency.
Ueda et al., in U.S. Patent Application 2007-0197717, describes a masonry treating agent comprising fluoromonomer having at least one acid group, and a non-fluorinated monomer. Ueda et al., teach copolymers containing long chain linear hydrocarbon (meth)acrylates and/or monomers containing a silicone containing groups to provide water, oil and soil resistance to masonry.
What is needed are coating copolymers that provide superior performance for acid etch resistance in addition to stain resistance, oil and water repellency to hard substrates. The present invention meets these needs.